Implant, in particular dental implant

ABSTRACT

A metal implant, in particular a dental implant, with a hydrophilic surface for at least partial insertion into a bone, and a method for the production of said implant are described. A particularly advantageous hydrophilic surface for improved osteointegration properties is made available if it is briefly treated, at least in some areas, in a weakly alkaline solution. These excellent osteointegration properties can be achieved in a method in which, optionally after a preceding mechanical surface modification by material removal and/or chemical surface modification, at least the areas exposed of this surface exposed to bone and/or soft tissue are chemically modified in an alkaline solution.

TECHNICAL FIELD

The invention concerns a metallic implant, preferably a dental implant,with a hydrophilic surface for the at least partial insertion into abone, as well as a method for its production.

BACKGROUND OF THE INVENTION

Injured or damaged parts of the hard and/or soft tissue of the humanbody are restored the best by using autologous hard and/or soft tissue.This is not always possible for various reasons, which is why in manycases synthetic material is used as a temporary (biodegradable orpost-operatively removable, respectively) or permanent replacementmaterial.

Implants which are anchored in hard and/or soft tissue, serve thetemporary or permanent replacement or the support of parts of themusculoskeletal system which have been damaged by accident, use,deficiency or disease, or which have been otherwise degenerated,including especially parts of the chewing apparatus. An implant normallyis defined as a synthetic chemically stable material, which isintroduced into the body as a plastic replacement or for mechanicalenforcement (see e.g. Roche Lexikon Medizin, Urban & Fischer (Pubis.);5^(th) edition 2003). The support- and replacement function in the bodyis taken over on the basis of the mechanical features and the implantdesign. Hence, for instance hip- and knee joint prostheses, spineimplants and dental implants have been clinically used successfully formany years.

For the anchoring of the implant and the compatibility of the implant atthe interface between the implant surface/neighboring tissue, theimplant surface has a great significance. Hence, measurements have shownthat implants with a smooth surface are anchored, almost independentlyof the basic material used, only a little in the bone (poorosteointegration), while implants with a structured surface enter into agood mechanical and, at a corresponding design of the surface, also agood biological connection with the surrounding hard- or soft tissue(see Titanium in Medicine, Material Science, Surface Science,Engineering, Biological Responses and Medical Applications Series:Engineering Materials, Brunette, D. M.; Tengvall, P.; Textor, M.;Thomsen, P. (Eds.)).

The time necessary for a sufficient incorporation, an important andcentral feature for implants, is termed osteointegration time, or, inthe dental implant field also osseointegration time, respectively.Thereby, the time is described, which passes by until the bone substancehas connected with sufficient force and durably with the implantsurface, so to speak, until it has virtually integrated into the implantsurface.

Various methods are used for surface treatment, see e.g. in A Guide toMetal and Plastic Finishing (Maroney, Marion L.; 1991); Handbook ofSemiconductor Electrodeposition (Applied Physics, 5) (Pandey, R. K., etal.; 1996); Surface Finishing Systems: Metal and Non-Metal FinishingHandbook-Guide (Rudzki, George J.; 1984); Titanium in Medicine, MaterialScience, Surface Science, Engineering, Biological Responses and MedicalApplications Series: Engineering Materials, (Brunette, D. M.; Tengvall,P.; Textor, M.; Thomsen, P. (Eds.)); and Materials and Processes forSurface and Interface Engineering (NATO Asi Series. Series E, AppliedSciences, 115, Pauleau, Ives (Editor); 1995); and the references citedtherein.

Besides the surface topology the osseointegration of the implant can beinfluenced by chemical coatings or modifications of the surface.Thereby, implants can be coated in an aqueous solution containingcalcium- and phosphate ions. The resulting surface consists of the twocalcium phosphate phases hydroxylapatite and bruschite. This coating ispost-operatively replaced by young bone directly on the implant surfacewithin 6-10 weeks and results in a very good healing incorporation ofthe implants (Zeggel P, Bioactive Calcium Phosphate Coatings for DentalImplants, International Magazine Of Oral Implantology, 1/2000).

The direct modification of an optimized rough surface with fluoride ontitanium implants is described as advantageous for the bone healingprocess by Ellingsen (Ellingsen, J. E. et al., Improved Retention andBone to Implant Contact with Fluoride Modified Titanium Implants Int. J.Oral Maxillofac Implants (2004); Vol. 19, p. 659-666).

A chemically active, hydrophilic implant surface on titanium implantscan be produced by a very elaborate conservation process in a nitrogenatmosphere. The storage of the surface in a solution of sodium chlorideconserves the hydrophilic features. Such a surface shall speed up theprocess of osseointegration and lead to a higher implant stability inthe early phase of osseointegration (Ferguson S. J. et al, Biomechanicalevaluation of the interfacial strength of a chemically modifiedsandblasted and acid-etched titanium surface, Journal of BiomedicalMaterials Research Part A Volume 78A, Issue 2, pages 291-297). Animalstudies of the hydrophilic surface show a significantly higherbone-implant contact compared to a hydrophobic surface at the samesurface topography (Buser D. et al, Enhanced Bone Apposition to aChemically Modified SLA Titanium Surface, J. Dent. Res. 83 (7) 529-533(2004).). These described hydrophilic features can only be produced in atechnologically elaborate way and conserved by a special way of storage,during prolonged contact with air the surface assumes a hydrophobicstate. Furthermore, the high costs for production and packaging and thelimited storage time in a saline solution are problematic for thistechnology.

From JP 2000-060958, a method is known, in which an implant is firstly,in a first step, treated with a highly concentrated sodium hydroxidesolution with a concentration of 5 mole/l, and then sintered under theinfluence of heat, and in a second step is treated with a calciumhydroxide solution with a concentration in the range of 0.1-20 mole/1during a time span of 10 min to three days at an increased temperatureof more than 50° C., followed by explicit washing. Thereby, presumablyapatite is produced on the surface, which is supposed to showadvantageous effects for the incorporation of the implant.

SUMMARY OF THE INVENTION

One object of the invention is therefore, to overcome the disadvantagesof the state of the art, and to propose implants, which have ahydrophilic surface and which are quickly and lastingly anchored inhard- and soft tissue and thereby show a good osteointegration orosseointegration, respectively. Specifically therefore, an improvedimplant with a preferably structured and chemically modified surface forthe at least partial insertion into hard tissue such as into a boneand/or into soft tissue shall be proposed, wherein the implant ismetallic. Furthermore, a suitable production method therefore shall beprovided. The solution to this problem is achieved in that the at leastsection-wise chemically modified and thereby hydrophilic surface is theresult of an alkaline surface treatment. Hence, this problem is solvedaccording to the invention, by a specifically treated surface of theimplant, said surface thereby having specific features, wherein thetreatment can be carried out over the entire surface of the implant aswell as on partial sections thereof. Within the scope of this invention,firstly implants are concerned, which are based on metallic materials.It is likewise possible to hydrophilize implants of ceramic basis underthe assistance of an alkaline treatment at the surface. This aspect isto be regarded virtually as a separate aspect, which has not beendescribed in the state of the art either, and which has inventivecharacter. Correspondingly, it is also possible to provide a ceramicimplant, which has a hydrophilic surface, which is at least section-wisetreated in an alkaline manner, or which is the result of a chemicalmodification, respectively. All embodiments described belowcorrespondingly could likewise be used on ceramic materials, such as forexample implants on the basis of zirconium oxide or aluminium oxide orcorresponding mixtures.

The terms hydrophilic and hydrophobic describe the wettability of asurface. Thereby, a surface is described as being hydrophilic, if it iswettable, the case of non-wetting is termed to be hydrophobic. Thehydrophilic or hydrophobic features can be determined quantatively bycontact angle measurements. Therein, the contact angle is defined as theangle which a fluid drop forms on the surface of a solid material tothis surface. When using water as a fluid, the surface is termed to behydrophilic for contact angles under 90°, and hydrophobic for contactangles over 90°. Implants with a rather hydrophilic surface show abetter and faster osseointegration (Ferguson S J, Broggini N, Wieland M,de Wild M, Rupp F, Geis-Gerstorfer J, Cochran D L, Buser D.: Biomedicalevaluation of the interfacial strength of a chemically modifiedsandblasted and acid-etched titanium surface; J Biomed mater Res A. 2006August; 78(2)291-7, as well as Rupp F, Scheideler L, Olshanska N, deWild M, Wieland M, Geis-Gerstofer J.: Enhancing surface free energy andhydrophilicity through chemical modification of microstructured titaniumimplant surfaces; J Biomed Mater Res A. 2006 February; 76(2):323-34.

The core of the invention thereby consists in that it has beensurprisingly determined that especially metal-based implants, but alsoceramic-based implants can be modified by the use of a specific alkalinetreatment on the surface, such that they afterwards show excellentosteointegration or osseointegration, respectively. It is shown that theosteointegration or osseointegration, respectively, of a therebyhydrophilized surface is better than the corresponding values for merelyblasted and acid-etched surfaces and/or surfaces, especially of metals,which were only provided with a macro- and micro-roughness bysand-blasting and etching.

Hence, the implant is modified at the surface by an alkaline treatment,wherein, especially preferably during the treatment in alkalinesolution, essentially exclusively a hydrophilization of the surface iscarried out. The treatment in the alkaline solution is carried outespecially without connecting an electrical potential, in other words,the implant is very simply immersed in the solution. The surfacetreatment leads to a hydrophilic surface, which remains hydrophilic fora certain time without additional elaborate storage. In other words, itis not about introducing for example only anions or cations from thealkaline solution into the basic material by the alkaline treatment, orto virtually effect a topographical abrasion, but it is actually aboutusing a chemical process which changes the hydrophilicity of the surfaceby the alkaline solution, in order to achieve a specifically hydrophilicsurface.

Actually, it is also found that the surfaces produced according to theinvention, in comparison to treatments according to the state of the artwith strongly alkaline solutions (normally in the range of 5M-20Mhydroxide-solutions) essentially do not show any topological ortopographical structural changes, respectively, which can be attributedto the alkaline treatment.

The hydrophilization of the surface preferably is carried out entirelyin an alkaline environment. The alkaline environment can be aqueous ororganic alkaline solutions. The surface treatment can possibly becoupled with a mechanically and chemically abrasive treatment for thecreation of the topography.

Additional or subsequent coatings, respectively, such as for example ofapatite, are not necessary and preferably not present either.

Furthermore, in contrast to the state of the art, post-treatments at ahigh temperature (e.g. treatment at 600° C. for several hours) or anelaborate rinsing (e.g. in the ultrasound bath) are not necessary. Thisis especially advantageous with cold-shaped materials, such as e.g.titanium, which otherwise would lose their mechanical properties.

Preferably, an aqueous or organic solution of one or morealkali-hydroxides (especially NaOH) is concerned, wherein preferably atotal concentration in the range of 0.05M-0.1M is used.

Alternatively or additionally, strontium can also be used. Hence, anaqueous or organic solution with a strontium-hydroxide can be concerned,wherein preferably a Sr-concentration in the range of 0.05M-0.1M isused.

The hydrophilic surface or the surface modified in an alkaline manner,respectively, is shown to be especially advantageous, if the implant isprovided with a coating of metal or metal oxide, respectively, or if, asis preferred, the implant essentially entirely consists of metal. Inthis context, it must be stressed that the surface of an implant oftitanium, zirconium, hafnium, tantalum, niobium, etc., as well as alloysformed thereof (see also below), after contact with oxygen, in otherwords for example when exposed to air, immediately forms a thinsuperficial layer of the corresponding oxide. Titanium-implants forexample have such a thin layer of titanium (IV)-dioxide (TiO₂), withsmall component parts of Ti₂O₃ and TiO. If metallic implants, or theirsurface, respectively, are mentioned below, this shall accordingly alsoencompass a surface with such an oxide layer. The metal can be ofvarious types, wherein these are known from the state of the art. Forexample, a metal can be used, which consists of pure titanium accordingto ISO 5832. Alternatively, it is possible to use metals, which areknown as implant steel according to ISO 5832. It is furthermore possibleto use titanium alloys, which comprise, besides titanium, aluminiumand/or vanadium and/or niobium. Metals based on cobalt chromium alloys,on cobalt chromium molybdenum alloys, on cobalt chromium tungsten nickelalloys and on cobalt nickel chromium molybdenum titanium alloys, arepossible. Furthermore, metals such as tantalum or magnesium or alloysbased on tantalum or magnesium, are possible.

According to a preferred embodiment, the implant is a dental implant,the surface of which, in an implanted state being exposed to the boneand/or soft tissue, is at least section-wise hydrophilized. Thehydrophilized surface can be created on a topographically pre-structuredsurface. This can be a sand-blasted surface and/or a surface modified byetching. Furthermore, the present invention concerns a process for theproduction of an implant, as is described above. The process ischaracterized in that an implant of metal (or also of ceramics) issurface-modified, possibly after an antecedent abrasive surfacemodification, especially for the creation of a macro- andmicro-roughness (e.g. also in a molten salt), at least in the areasexposed to the bones and/or soft tissue, by the help of an alkalinesurface treatment.

Specifically, the process is for the production of a metallic implantwith a hydrophilic surface for the at least partial insertion into hardtissue, such as into a bone and/or into soft tissue, characterized inthat the process comprises at least one step, in which at least an areadesignated for the partial insertion into hard tissue, such as into abone and/or into soft tissue, is subjected to a short-time treatment,possibly after an antecedent mechanically and/or chemically especiallyabrasive surface modification, in an aqueous or organic solution ofalkali- and/or alkaline-earth-hydroxides, or a mixture of thesehydroxides, with a total concentration of alkali- and/oralkaline-earth-hydroxide in the range of 0.005M-0.5M. Concentrations inthis range are preferred, however, the bottom limit can also lie at0.008 M, preferably at 0.01 M. Concerning the upper limit, it can alsolie at 0.4 M, or at 0.3 M, wherein an upper limit of 0.2 M or 0.1 M ispreferred, or especially 0.07 M or 0.05 M. Said bottom limits and upperlimits can be combined correspondingly.

A first preferred embodiment is characterized in that, as describedabove, metal oxides are modified at the surface in the step of alkali-and/or alkaline-earth-hydroxide treatment.

Preferably, an alkaline solution of essentially alkali hydroxides, suchas e.g. of potassium hydroxide and/or sodium hydroxide, is used. Smallcomponent parts, typically in the range of less than 5% or even lessthan 2%, of other salts (not only, but preferably of the ones mentionedabove) or other additives, can be additionally present for the settingof the hydrophilization conditions.

Preferably, the alkaline solution is an aqueous solution, exclusivelyconsisting of one or more of said hydroxides.

A further preferred embodiment is characterized in that in an aqueoussolution of alkali- and/or alkaline-earth-hydroxides, or a mixture ofthese hydroxides, with a total concentration of alkali- and/oralkaline-earth-hydroxide in the range of 0.05M-0.1M, is subjected to ashort-term treatment. Generally, it is preferred that the treatment iscarried out during a comparably short time span, e.g. in the range of 1sec-30 min. It is even possible that the treatment takes place during atime span of in the range of 2 sec-10 min, preferably of 5 sec-120 sec,especially preferably of 5-30 sec.

It is furthermore preferred that the treatment is allowed to take placein an aqueous solution of alkali- and/or alkaline-earth-hydroxides, or amixture of these hydroxides, at a temperature in the range of −10-110°C., preferably in the range of 10-30°.

A further preferred embodiment is characterized in that the aqueoussolution is a solution of sodium hydroxide. Preferably in aconcentration of 0.01-0.1 mole, preferably of 0.01-0.07 mole, whereinthe treatment preferably is carried out in a range of −10-100° C.,especially in the range of 10-30° C. (e.g. RT).

As already mentioned, the process is characterized in that the implantsurface can be stored and/or packaged and/or implanted after thetreatment with the aqueous solution without any post-treatment at anincreased temperature and/or post-treatment by rinsing.

A further embodiment concerns a storage method, which is characterizedin that the implant surface is stored and packaged after the treatmentwith the aqueous solution in an alkaline solution. The alkaline solutioncan be a solution of preferably exclusively alkali- and/oralkaline-earth-hydroxides, or a mixture of these solutions, especiallypreferably an aqueous solution of sodium hydroxide, preferably at aconcentration of 0.0001-0.9 mole.

A further preferred embodiment is characterized in that before thetreatment in the aqueous solution a mechanically abrasive surfacemodification in the form of a blast-treatment is carried out, especiallyby sand-blasting, preferably by the use of aluminium oxide-particleswith an average particle size of 0.05-0.25 mm or 0.25-0.5 mm, especiallypreferably with a pressure between 1-10 bar, preferably between 1-6 bar,especially preferably between 2-5 bar. Alternatively or additionally, itis possible, prior to the treatment in the aqueous solution and possiblyafter such a mechanically abrasive surface modification, to carry out achemical surface modification, especially by the treatment withpreferably concentrated sulphuric acid and/or hydrochloric acid and/orhydrofluoric acid and/or nitric acid or mixtures thereof, preferably ata temperature above room temperature.

The process according to a further embodiment can be characterized inthat the aqueous solution is degassed prior to the use as an immersionbath for the implant, especially such that carbonates are removed fromthe solution. In order to maintain this carbonate-free state, thesolution can be stored preferably under an inert gas atmosphere untiluse.

For the further improvement of the modification of the surface, inaddition, ultrasound can generally be connected at least period-wise inthe solution during the treatment. It possibly suffices to hold thecontainer with the solution to the wall of an ultrasound bath,preferably the container with the solution for the immersion of theimplant is immersed into an ultrasound bath. It is generally shown thatit is advantageous to subject the bath to mechanical vibrations duringthe treatment. An alternative possibility is to use the piezoelectricultrasound hand-held devices usually available in a dentists' practice(for example for dental cleaning), be it that they are immersed in thebath or are held to the container.

Alternatively or additionally, it is furthermore possible to irradiatethe implant with UV-light prior to and/or during and/or after thetreatment in the solution.

For certain materials, it is found not to be very easy, also afterprolonged storage, to ensure the hydrophilic surface enduringly.Accordingly, the present invention also concerns a method, which ischaracterized in that an implant, possibly after an antecedentmechanically and/or chemically abrasive surface modification, and whichoptionally (but in no way mandatorily) has already been treated in anaqueous or organic solution of alkali- and/or alkaline-earth-hydroxidesas described above, is sterilely packaged and packaged together with acontainer containing an aqueous or organic solution of alkali- and/oralkaline-earth-hydroxides, or a mixture of these hydroxides, with atotal concentration of alkali- and/or alkaline-earth-hydroxide in therange of 0.005M-0.5M, as described above. Then the implant, afterremoval from the package, can be treated in the container by a processas described above, just shortly before its insertion into the humanbody, followed by insertion.

It can generally be of advantage if the storage of the either alreadytreated or not yet treated implant takes place in the dark.Correspondingly, it is preferred, if the container is a container inwhich the implant is protected from light.

Correspondingly, the present invention also concerns, in the sense of akit of parts, a combination package containing at least one (sterilely)packaged implant, especially preferably a dental implant, said implantpossibly having been subjected to an antecedent mechanically and/orchemically abrasive surface modification, and/or optionally treated inan aqueous or organic solution of alkali- and/oralkaline-earth-hydroxides as described further above, said packagefurther containing at least one container with a sterilely packagedaqueous or organic solution of alkali- and/or alkaline-earth-hydroxides,or a mixture of these hydroxides, with a total concentration of alkali-and/or alkaline-earth-hydroxide in the range of 0.005M-0.5M, in otherwords essentially with a solution as used in the context of the abovedescribed process. Preferably, such a combination package ischaracterized in that the container contains an aqueous solution ofsodium hydroxide at a concentration of 0.008-0.4 mole, preferably of0.01-0.1 mole, especially preferably of 0.01-0.07 mole, wherein thissolution possibly is rinsed with an inert gas prior to the bottling forthe removal of CO₂ from the solution.

Furthermore, the invention concerns a metallic (or ceramic) implant witha hydrophilic surface for the at least partial insertion into hardtissue, such as into a bone, and/or into soft tissue, characterized inthat the hydrophilic metal oxide surface is at least section-wisemodified in an alkaline-, preferably weakly alkaline manner.

Furthermore, the invention concerns a metallic (or ceramic) implant witha hydrophilic surface for the at least partial insertion into hardtissue, such as into a bone, and/or into soft tissue, producible orproduced by a method as described above. The implant preferablyconsists, at least at the surface or preferably entirely, of metal oxideand/or metal.

The implant preferably contains titanium and/or titanium oxide, whichpossibly additionally is alloyed with aluminium and niobium, and/orwherein this alloy contains vanadium instead of niobium.

Preferably, the implant is a dental implant, the surface of which, inthe implanted state, being exposed to the bone and/or soft tissue, ishydrophilized in an alkaline manner.

The hydrophilic surface is preferably at least section-wise macro-rough,especially modified by sand-blasting and micro-rough, especiallyacid-etched.

Furthermore, the invention concerns a use of such an implant, especiallyproduced as described above, as a dental implant, especially as a crownstub, as a threaded piece, a screw and/or a pin.

Further preferred embodiments of the invention are described in thedependent claims.

SHORT DESCRIPTION OF THE FIGURES

The invention shall be further illustrated below by embodiments inconnection with the figures, in which:

FIG. 1 shows the dependence of the surface hydrophilization (contactangle) on the concentration of the alkaline solution used;

FIG. 2 shows the dependence of the surface hydrophilization (contactangle) on the concentration of the alkaline solution used after storagein air without additional stabilization;

FIG. 3 shows the dependence of the surface hydrophilization (contactangle) on the concentration of the alkaline solution used after storagein alkaline environment;

FIG. 4 shows the in vivo results of experiments carried out with twodifferent material- and surface implant types;

FIG. 5 shows XPS-measurements on an untreated sample (U) and on acomparative sample (V) according to JP 2000-060958;

FIG. 6 shows XPS-measurements on NaOH-treated samples according to theinvention;

FIG. 7 shows XPS-measurements on Sr(OH)₂-treated samples according tothe invention;

FIG. 8 shows XPS-measurements in detail in the range of titanium onsamples a) untreated (U); b) according to JP 2000-060958 (V); c) treatedwith NaOH according to the invention; d) treated with Sr(OH)₂ accordingto the invention;

FIG. 9 shows Raman-spectra of the comparative samples according to JP2000-060958;

FIG. 10 shows Raman-spectra of NaOH-treated samples according to theinvention;

FIG. 11 shows Raman-spectra on Sr(OH)₂-treated samples according to theinvention;

FIG. 12 shows comparative Raman-spectra; and

FIG. 13 shows photographs of the wetting of implants with blood, a)implant not treated according to the invention, b) implant treatedaccording to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention describes the possibility to chemically modify thesurface of implants, which especially are produced from metallic- butalso of ceramic materials. Aim of the surface modification are a betteranchoring of the implants into hard tissue, a better bond between hardtissue and implant surface, a better bond between soft tissue andimplant surface, and a better interaction of the implant surface on theinterface between implant surface and hard tissue and/or soft tissue.

Preferably, the invention concerns implants, which are anchored in hard-and/or soft tissue and which serve the temporary or permanentreplacement or support of accident-, use-, deficiency- ordisease-damaged or otherwise degenerated parts of the musculoskeletalsystem, including the chewing apparatus, especially the dental area withthe corresponding, also aesthetic aspects. Hence, for example hip- andknee joint prostheses, spine implants and dental implants have been usedclinically for many years. The problem of the improved osteointegrationfeatures, or osseointegration features, respectively, is solvedaccording to the invention by a corresponding surface treatment of the(metal oxide-) surface of the implant, wherein the treatment can becarried out over the entire implant surface as well as over partialareas of the implant surface. By way of such a surface treatment, it isensured that the metals, such as preferably titanium and its alloys, arebetter integrated in the hard- and/or soft tissue.

The structural and functional anchoring, e.g. of a dental implant, inthe bone, normally is achieved by applying a macro-roughness, and/or apossibly additional micro-roughness. The macro-roughness can for examplebe obtained by a mechanical blasting process, the subsequentmicro-roughness for example in an additive process by plasma technique,or in a subtractive process by chemical etching on the surface. Thedegree of anchoring of the implant in the bone can be determined withmechanical measurements. Numerous tests have shown that a sufficientanchoring of an implant in the bone depends to a great extent on thesurface condition of the implant, especially on the roughness and thechemical environment at its surface.

The present invention describes a specific and newly created (chemicalenvironment for a) hydrophilic surface for the better osteointegrationof implants, which are produced of metal, preferably of titanium and itsalloys. This biologically effective surface according to the inventioncan be produced by the use of an alkaline solution, possibly incombination for example with additional mechanical conditioning andstructuring, grit blasting, sand blasting and/or subsequent orantecedent chemical treatment, for example etching with acid or similar,or by a combination of such processes.

The surface according to the invention can for example be produced byapplying the desired roughness or texture, respectively, to the surface.The implant can especially be produced by grit-blasting or sand-blastingthe implant surface, and/or structuring it by the use of plasmatechnique, and subsequently treating the surface with a chemical processwith an alkaline solution until a corresponding hydrophilic surface hasbeen obtained.

As mentioned, the implant is treated with a base or an aqueous ororganic alkaline solution, respectively. Bases, according to thedefinition of Brönsted, are compounds, which take up protons. Accordingto Lewis, bases are molecules or ions with a lone electron pair or anelectron-rich multiple bond. The strength of bases can for example bedefined over the pKb-value.

However, bases or alkaline solutions have never found application in thepresent context for the stable hydrophilization of an implant surface inthe surprisingly determined concentration range.

It is surprisingly shown that especially with implants on the basis ofmetal, alkaline solutions result in an excellent hydrophilization of thesurface, which is advantageous for the integration in bones or softtissue, respectively. Preferably, the surface is hydrophilized with asolution of sodium hydroxide in the present application. However,besides the use of a solution of a hydroxide, it is also possible to usesolutions on the basis of various hydroxides.

For example aqueous alkaline solutions, preferably of potassiumhydroxide or sodium hydroxide, are shown to be especially suitable,wherein the concentration is set in the range of 0.0001 mole to 0.9mole, preferably in the range of 0.001 to 0.1. It turns out to beespecially suitable if the concentration is chosen in the range of 0.01to 0.07 M. With such weakly alkaline solutions, especially of saidcomponents, the treatment is preferably carried out at a temperature inthe range of −10°-100° C., especially at a temperature in the range of10° C.-30° C.

It can generally be said that typically an alkaline solution with aconcentration in the range of 0.001-0.09 M can be used, preferably inthe range of 0.01-0.09 M, preferably at a concentration in the range of0.01-0.07 M.

According to a further preferred embodiment of the method according tothe invention, the surface is exposed at least partially over a timespan of 2 seconds to 1 hour, preferably from 5 seconds to 10 minutes,especially from 5 seconds to 1 minute, to an alkaline solution, e.g. inthe form of a bath. Preferably, a treatment duration of less than onehour, more preferably of at least 5 seconds is used, in order toactually ensure a sufficient hydrophilization of the implant by thealkaline solution.

With implants pre-treated that way, a secure bond to hard- and softtissue can be created.

EXPERIMENTAL PRODUCTION OF IMPLANTS Example 1

A common form of a dental implant in the form of a screw of a diameterof 3.5 mm and of a length of 10 mm was produced from titanium cp degree4. The surface to be inserted into the bone was then provided with amacro-roughness, by sand-blasting it with a particle of Al₂O₃ at about 4bar. Subsequently, the roughened surface was etched at high temperaturewith a mixture of hydrochloric acid and sulphuric acid, in order toobtain a micro-structuring. After the etching, the implant was treatedwith pure/deionised water and then washed and rinsed in deionised water.Subsequently, the implant was immersed into an aqueous 0.05 MNaOH-solution for 10 seconds. After the surface was air-dried, one wasable to qualitatively determine, by complete wetting with a drop ofwater, that the surface behaves in a hydrophilic manner.

Example 2

A common form of a dental implant in the form of a screw of a diameterof 3.5 mm and of a length of 10 mm was produced from titanium cp degree4. The surface to be inserted into the bone was then provided with amacro-roughness, by sand-blasting it with a particle of Al₂O₃ at about 4bar. Subsequently, the roughened surface was etched at high temperaturewith a mixture of hydrochloric acid and sulphuric acid, in order toobtain a micro-structuring. After the etching, the implant was treatedwith pure/deionised water and then washed and rinsed in deionised water.Subsequently, the implant was immersed into an aqueous 0.05 MNaOH-solution for 10 seconds. After the surface was air-dried, theimplant was stored at room temperature in air for 4 weeks. Subsequently,one was able to qualitatively determine, by complete wetting with a dropof water, that the surface behaves in a hydrophilic manner.

Example 3

A common form of a dental implant in the form of a screw of a diameterof 3.5 mm and of a length of 10 mm was produced from titanium cp degree4. The surface to be inserted into the bone was then provided with amacro-roughness, by sand-blasting it with a particle of Al₂O₃ at about 4bar. Subsequently, the roughened surface was etched at high temperaturewith a mixture of hydrochloric acid and sulphuric acid, in order toobtain a micro-structuring. After the etching, the implant was treatedwith pure/deionised water and then washed and rinsed in deionised water.Subsequently, the implant was immersed into an 0.05 M NaOH for 10seconds. Subsequently, the implant was stored in an aqueous 0.01MNaOH-solution at room temperature for 4 weeks. The NaOH-solution wasrinsed with N₂ beforehand, in order to remove CO₂ from the solution andto avoid a formation of carbonate during storage. Subsequently, one wasable to qualitatively determine, by complete wetting with a drop ofwater, that the surface behaves in a hydrophilic manner.

Example 4

Titanium in the form of platelets with a diameter of 15 mm was producedfrom titanium cp degree 4. The surface of the sample bodies was thenprovided with a macro-roughness, by sand-blasting it with a particle ofAl₂O₃ at about 4 bar. Subsequently, the roughened surface was etched athigh temperature with a mixture of hydrochloric acid and sulphuric acid,in order to obtain a micro-structuring. After the etching, the samplebodies were treated with pure/deionised water and then washed and rinsedin deionised water. Subsequently, the sample bodies were immersed intovarious aqueous concentrations of NaOH for about 10 seconds. Afterair-drying the surface for 40 minutes, one was able to quantitativelydetermine, by contact angle measurements, at which concentration thetransition from hydrophobic to hydrophilic behaviour takes place.

FIG. 1 shows the dependency of the surface hydrophilization (contactangle) on the concentration of the alkaline aqueous solution used. It isshown that, starting at completely unexpectedly low concentrations ofabout 0.005 M, a substantial effect occurs, and that these unexpectedlylow concentrations allow a treatment without post-treatment.Post-treatments (rinsing, heat, etc.) are usually necessary atconcentrations of 1 M and higher.

Example 5

Titanium in the form of platelets with a diameter of 15 mm was producedfrom titanium cp degree 4. The surface of the sample bodies was thenprovided with a macro-roughness, by sand-blasting it with a particle ofAl₂O₃ at about 4 bar. Subsequently, the roughened surface was etched athigh temperature with a mixture of hydrochloric acid and sulphuric acid,in order to obtain a micro-structuring. After the etching, the samplebodies were treated with pure/deionised water and then washed and rinsedin deionised water. Subsequently, the sample bodies were immersed intovarious aqueous concentrations of NaOH for about 10 seconds. Afterair-drying the surface, the implant was stored for 4 weeks in air at 30%humidity at room temperature in the dark. Subsequently, one was able toquantitatively determine, by contact angle measurements, at whichconcentration in water the transition from hydrophobic to hydrophilicbehaviour takes place.

FIG. 2 shows the dependency of the surface hydrophilization (contactangle) on the concentration of the alkaline solution used after suchstorage in air.

Example 6

Titanium in the form of platelets with a diameter of 15 mm was producedfrom titanium cp degree 4. The surface of the sample bodies was providedwith a macro-roughness, by sand-blasting it with a particle of Al₂O₃ atabout 4 bar. Subsequently, the roughened surface was etched at hightemperature with a mixture of hydrochloric acid and sulphuric acid, inorder to obtain a micro-structuring. After the etching, the samplebodies were treated with pure/deionised water and subsequently washedand rinsed in deionised water. Subsequently, the sample bodies wereimmersed in various aqueous concentrations of NaOH for about 10 seconds.Subsequently, the implant was stored for 4 weeks in 0.01 M NaOH at roomtemperature. The aqueous NaOH-solution was rinsed with N₂ beforehand, inorder to remove CO₂ from the solution and to avoid a formation ofcarbonate during the storage. The samples were subsequently removed fromthe bath and dried for 40 minutes. Subsequently, one was able toquantitatively determine, by contact angle measurements, at whichconcentration the transition from hydrophobic to hydrophilic behaviourtakes place.

FIG. 3 shows the dependency of the surface hydrophilization (contactangle) on the concentration of the alkaline solution used after storagein an alkaline environment.

Example 7

A common form of a dental implant in the form of a screw of a diameterof 3.5 mm and of a length of 10 mm was produced from zirconium oxide.The blank shape was made from a cylindrical ceramic blank in an actuallyknown manner of mechanical ceramic treatment, mainly by grinding. Thesurface to be inserted into the bone was then provided with amacro-roughness, by sand-blasting it with a particle of Al₂O₃ of themedium particle size of 0.1-0.15 mm at about 3 bar. Subsequently, theroughened surface (macro-roughness) was treated with a mixture ofpotassium hydroxide and sodium hydroxide in a molten salt with a ratioof KOH:NaOH of 1:1 at a temperature of over 190° C. for about 30 hours.After the etching, the implant was treated with pure/deionised water inultrasound and subsequently washed and rinsed in deionised water.

Subsequently, the implant was immersed into an aqueous 0.05 MNaOH-solution for 10 seconds. Subsequently, the implant was stored in0.01 M NaOH at room temperature for 4 weeks. The NaOH-solution wasrinsed with N₂ beforehand, in order to remove CO₂ from the solution andto avoid a formation of carbonate during the storage. Subsequently, onewas able to qualitatively determine, by complete wetting with a drop ofwater, that the surface behaves in a hydrophilic manner.

Example 8

A common form of a dental implant in the form of a screw of a diameterof 3.5 mm and of a length of 10 mm was produced from zirconium oxide.The blank shape was made from a cylindrical ceramic blank in an actuallyknown manner of mechanical ceramic treatment, mainly by grinding. Thesurface to be inserted into the bone was then provided with amacro-roughness, by sand-blasting it with a particle of Al₂O₃ of themedium particle size of 0.1-0.15 mm at about 3 bar. Subsequently, theroughened surface (macro-roughness) was treated with a mixture ofpotassium hydroxide and sodium hydroxide in a molten salt with a ratioof KOH:NaOH of 1:1 at a temperature of over 190° C. for about 30 hours.After the etching, the implant was treated with pure/deionised water inultrasound, and then washed and rinsed in deionised water. After theetching, the implant was treated with pure/deionised water and thenwashed and rinsed in deionised water.

Subsequently, the implant was immersed into an aqueous 0.05 MNaOH-solution for 10 seconds. After air-drying of the surface, theimplant was stored in air at room temperature for 4 weeks. Subsequently,one was able to qualitatively determine, by complete wetting with a dropof water, that the surface behaves in a hydrophilic manner.

Example 9

Titanium dental implants were produced from titanium cp degree 4. Thesurface of the implants was then provided with a macro-roughness, bysand-blasting it with a particle of Al₂O₃ at about 4 bar. Subsequently,the roughened surface was etched at a high temperature with a mixture ofhydrochloric acid and sulphuric acid in order to achieve amicro-structuring. After the etching, the implants were treated withpure/deionised water and then washed and rinsed in deionised water.Subsequently, the implants were not treated any further yet andindividually packaged. They were subsequently packaged together at atime in a combination package, with a separate, sterilely closedcontainer containing an aqueous NaOH-solution with variousconcentrations in the range of 0.005-0.5M, preferably 0.005-0.07M.Therein, the size and filling of the container was chosen such thatafter unpacking the implant was able to be laid into the container, andto subsequently be kept therein for a certain period of time, withoutany solution escaping over the rim during immersion and wherein theimmersed implant ended up lying entirely in the solution with its areato be treated. These combination packages (kit of parts) weresubsequently stored for a time span of several weeks.

Shortly before use (for example in the operating room), the implant isunpacked and the container opened (removal of lid), and the implant issubsequently laid into the container, wherein it immerses into thesolution entirely for about 10-30 seconds with its area to be treated.After the (optional) air-drying of the surface for several minutes, onewas able to qualitatively determine, by complete wetting with a drop ofwater, that the surface behaves in a hydrophilic manner, and that thestill humid or dried implant is ready for its insertion into the humanbody.

It is by the way also thinkable that the NaOH-solution first is providedin an ampulla in the combination package, and that the solution first ispoured into a container provided by the end-user.

Example 10

Titanium dental implants were produced from titanium cp degree 4. Thesurface of the implants was then provided with a macro-roughness, bysand-blasting it with a particle of Al₂O₃ at about 4 bar. Subsequently,the roughened surface was etched with a mixture of hydrochloric acid andsulphuric acid at high temperature in order to achieve amicro-structuring. After the etching, the implants were treated withpure/deionised water and then washed and rinsed in deionised water.Subsequently, the implants were not treated any further yet andindividually packaged. They were subsequently packaged together at atime in a combination package, with a separate, sterilely closedcontainer containing an aqueous NaOH-solution with variousconcentrations in the range of 0.005-0.5M, preferably 0.005-0.07M.Therein, the size and filling of the container was chosen such thatafter unpacking, the implant was able to be laid or placed into thecontainer or to be held by an instrument, and to subsequently be kepttherein for a certain time, without any solution escaping over the rimduring immersion and wherein the immersed implant ended up lyingpartially or entirely in the solution. These combination packages (kitof parts) were subsequently stored during a time span of several weeks.Shortly before use (for example in the operating room), the implant isunpacked and the container opened (removal of lid), and the implant issubsequently laid into the container, wherein it partially or entirelyimmerses into the solution for about 10-30 seconds. The containercontaining NaOH is exposed to an ultrasound excitation in an ultrasoundbath and (possibly to general mechanical vibrations) during treatment.After the (optional) air-drying of the surface for several minutes, onewas able to qualitatively determine, by complete wetting with a drop ofwater, that the surface behaves in a hydrophilic manner, and that thestill humid or dried implant is ready for its insertion into the humanbody.

The impressive change of the surface was verified in these samples bywetting with blood, and said wetting was photographically captured forimplants not dried (see FIG. 13), in comparison to an implant nottreated at the surface.

Example 11

Titanium dental implants were produced from titanium cp degree 4according to example 10 and post-treated. The container containing NaOHhowever is now not exposed to an ultrasound excitation in an ultrasoundbath during treatment, but is exposed to UV-radiation. After the(optional) air-drying of the surface for several minutes, one was ableto qualitatively determine, by complete wetting with a drop of water,that the surface behaved in a hydrophilic manner, and that the stillhumid or dried implant is ready for its insertion into the human body.

Example 12

A common form of a dental implant in the form of a screw of a diameterof 3.5 mm and of a length of 10 mm was produced from titanium cp degree4 and the surface to be inserted into the bone was treated according toexample 10. After the (optional) air-drying of the surface for severalminutes, one was able to qualitatively determine, by complete wettingwith a drop of water, that the surface behaves in a hydrophilic manner,and that the still humid or dried implant is ready for its insertioninto the human body.

Example 13

Disks with a diameter of 15 mm were produced from titanium cp degree 4.The surface comparable to an implant, said surface to be inserted in thebone, was then provided with a macro-roughness, by sand-blasting it witha particle of Al₂O₃ at about 4 bar.

Subsequently, the roughened surface was etched with a mixture ofhydrochloric acid and sulphuric acid at high temperature in order toachieve a micro-structuring. After the etching, the implant was treatedwith pure/deionised water and then washed and rinsed in deionised water.

Subsequently, a part of the titanium disks were treated according to JP2000-060958, discussed above, in the sense of a comparative experiment(V). For this purpose, the samples were immersed in a mixture of 1.5 MNaOH, 1.5 M KOH at a ratio of 1:1 for 24 h at 50° C. in a closedcontainer, and subsequently calcinated at 200° C. for 3 hours. After theprobes cooled off, they were immersed according to JP 2000-060958 in 10mM Ca(OH)₂-solution at 80° C. for 1 h, subsequently shortly rinsed inDI-water and dried. The samples thus treated according to JP 2000-060958were subjected to XPS and ramanspectroscopical tests.

The other part of the titanium disks, prepared as mentioned above, weresubjected to the treatment according to the invention (see e.g. example10). For this purpose, six titanium disks at a time were treated(immersed) with NaOH of concentrations of 0.01; 0.05; 0.005M for 10seconds each. Furthermore, six titanium disks at a time were treated(immersed) with Sr(OH)₂ of the concentrations for 10 seconds each. Forthis purpose, the container with the NaOH or Sr(OH)₂-solution,respectively, was each located in a switched-on ultrasound bath. Thesamples thus treated according to the invention were also subjected toXPS and ramanspectroscopical tests and compared with the results of thesamples treated according to JP 2000-060958.

The tests show the expected clear differences between the hydrophilizingtreatment according to the invention and the chemically and structurallysurface changing treatment according to JP 2000-060958. Thequantification of the XPS-measurements, wherein each sample is measuredon two different locations, shows unambiguous differences in thechemical composition of the surface, as can be seen in the followingtable.

TABLE 1 Quantitative analysis of the XPS-measurements AtomicConcentration [%] Samples JP 2000-060958 C 1s Ca 2p Mg 2p Na KLL O 1s Ti2p V Sample 1 26.3 6.5 2.9 0.4 52.3 11.7 V Sample 1 27.9 6.3 2.0 0.451.1 12.2 V Sample 2 27.4 6.6 2.3 0.4 52.1 11.2 V Sample 2 26.6 6.2 3.70.3 52.4 10.8 Atomic Concentration [%] Samples NaOH C 1s N 1s Na KLL O1s Ti 2p Zn 2p NaOH 0.01M Sample 1 18.6 2.7 8.5 49.1 20.7 0.4 NaOH 0.01MSample 1 18.3 1.8 8.7 50.4 20.3 0.5 NaOH 0.01M Sample 2 18.5 1.9 9.050.5 19.8 0.4 NaOH 0.01M Sample 2 19.3 2.5 8.4 48.6 20.8 0.3 NaOH 0.05MSample 1 18.8 1.9 10.2 49.7 19.0 0.3 NaOH 0.05M Sample 1 18.6 2.1 10.949.9 18.1 0.4 NaOH 0.05M Sample 2 19.2 1.8 13.7 49.2 15.9 0.2 NaOH 0.05MSample 2 19.6 1.8 13.4 49.1 15.9 0.2 NaOH 0.005M Sample 1 20.3 2.0 8.649.9 18.6 0.6 NaOH 0.005M Sample 1 20.4 1.6 6.7 49.9 20.9 0.5 NaOH0.005M Sample 2 18.3 2.4 6.0 51.4 21.7 0.4 NaOH 0.005M Sample 2 19.3 2.46.0 50.0 22.1 0.2 Atomic Concentration [%] Samples Sr(OH)2 C 1s Ca 2p N1s O 1s Sr 3d Ti 2p Zn 2p Sr(OH)2 0.01M 24.2 2.0 2.8 51.0 6.0 13.6 0.5Sample 1 Sr(OH)2 0.01M 17.1 0.7 2.4 52.8 2.3 24.3 0.5 Sample 1 Sr(OH)20.01M 19.0 0.4 3.5 50.5 2.2 24.2 0.3 Sample 2 Sr(OH)2 0.01M 18.5 0.3 2.352.4 2.5 23.8 0.3 Sample 2 Sr(OH)2 0.05M 15.5 1.5 2.3 56.0 5.1 19.6 0.0Sample 1 Sr(OH)2 0.05M 18.5 1.6 1.9 53.4 7.1 17.2 0.3 Sample 1 Sr(OH)20.05M 14.6 1.3 1.5 57.9 5.2 19.2 0.3 Sample 2 Sr(OH)2 0.05M 19.8 1.6 1.352.9 7.0 17.4 0.0 Sample 2 Sr(OH)2 0.005M 17.4 0.6 2.8 52.4 1.7 24.8 0.4Sample 1 Sr(OH)2 0.005M 17.3 0.4 2.3 52.5 1.8 24.8 0.8 Sample 1 Sr(OH)20.005M 20.5 0.5 3.0 50.1 2.1 23.2 0.6 Sample 2 Sr(OH)2 0.005M 19.4 0.82.8 50.8 2.9 22.8 0.5 Sample 2

The samples treated according to the invention show significantly moretitanium on the surface than the samples treated according to JP2000-060958 and, according to the treatment, a significant portion of Naor Sr, respectively, on the surface, said portion not being present onthe surface of titanium disks according to JP 2000-060958.

Contrarily, the samples treated according to JP 2000-060958 have asignificantly higher portion of Ca on the surface.

The XPS-spectra themselves are shown in FIGS. 5 to 8. FIG. 5 shows thespectrum of the samples treated according to JP 2000-060958 as comparedto a non-hydrophilized (untreated) sample. FIG. 6 shows the spectra ofthe samples treated with NaOH according to the invention and FIG. 7shows the samples treated with Sr(OH)₂ according to the invention. Thedifference concerning Ca, already being clear from the quantification,are clearly shown, and furthermore the different binding energies fortitanium.

Therefore, the detailed spectra were additionally measured for titanium.In FIG. 8, it is clearly visible that the surface treatment according toJP 2000-060958 leads to a change in the chemical environment oftitanium.

Contrary thereto, the samples which were surface-treated according tothe invention do not show any change in the chemical environment oftitanium as to the non-hydrophilized (untreated) surface also shown inthe figure.

Experiments by Ramanspectroscopy also show differences between thehydrophilizing treatment according to the invention and the chemicallyand structurally surface changing treatment according to JP 2000-060958.

In the spectra of the comparative probes 1-1 and 1-2, FIG. 9, (JP2000-060958 treatment), the broad peaks are observed at 261 cm-1,433-cm-1, and 663 cm-1, as well as the step at 899 cm-1. These cannot beassigned to the crystalline phases of the titanium oxide (anatase,rutile or brookite) and also not unambiguously to calcium carbonate,calcium titanate or even apatite (contrary to the statement in JP2000-060958). It probably concerns an amorphic titanium oxide.

Contrarily, no Raman peaks at all are detected in the spectra of thehydrophilized samples, as can be seen in FIGS. 10 and 11. Therefore, noRaman-active compounds can be detected on the surface of the samples.

The Raman-spectra of the samples treated according to JP 2000-060958generally differ from the Raman-spectra of all hydrophilized samples,which are comparable among each other, as can be seen in FIG. 12.

In Vivo-Tests:

It has been shown with all exemplarily produced samples with ahydrophilic surface (examples 1 to 13), that the osseointegration or theosteointegration, respectively, was effected well. Furthermore, also agood integration on soft tissue (e.g. gum) is shown. FIG. 4 showscorresponding results of two experiments conducted with two differentmaterials and surface implant types. Therein, a titanium implant with adiameter of 4.2 mm and a length of 8 mm with a surface producedaccording to the invention essentially according to the above mentionedexample 1 (measurement 1 in FIG. 4, on the left) and an accordinglydimensioned dental implant with a plasma-chemically anodically oxidizedsurface (measurement 2 in FIG. 4, on the right) of a titanium implantwere compared. The plasma-chemically anodically oxidized surfacecorresponds to the surface of commercially very prevalent and often usedimplants. After a healing time of 2 weeks, the removal torque wasdetermined, which was necessary to loosen the grown-in implants from thebone. As shown in FIG. 4, a better in-growth of the new implant wasdetected.

Histological measurements furthermore show unambiguously better contactareas (BIC, bone to implant contact) as compared to the implants nottreated according to the invention.

1. Method for the production of a metallic implant with a hydrophilicsurface for at least partial insertion into hard tissue such as into abone and/or into soft tissue, wherein the method comprises at least onestep, in which at least one area, which is provided for partialinsertion into hard tissue as into a bone and/or into soft tissue, issubjected, optionally after an antecedent mechanically and/or chemicallyabrasive surface modification, to a short-time treatment in an aqueousor organic solution of alkali- and/or alkaline-earth-hydroxides, or amixture of these hydroxides, with a total concentration of alkali-and/or alkaline-earth-hydroxide in the range of 0.005M-0.5M.
 2. Methodaccording to claim 1, wherein the solution is an aqueous or organicsolution of one or more alkali-hydroxides, wherein a total concentrationin the range of 0.05M-0.1M is used.
 3. Method according to claim 1,wherein the solution is an aqueous or organic solution with astrontium-hydroxide, wherein a concentration in the range of 0.05M-0.1Mis used.
 4. Method according to claim 1, wherein in the step of thealkali- and/or alkaline-earth-hydroxide treatment, metal oxides aremodified at the surface.
 5. Method according to claim 1 or 2, whereinthe alkaline solution is an aqueous solution consisting exclusively ofone or more of the named hydroxides.
 6. Method according to claim 1,wherein the short-term treatment is carried out in an aqueous solutionof alkali- and/or alkaline-earth-hydroxides, or a mixture of thesehydroxides, with a total concentration of alkali- and/or earth-alkalihydroxide in the range of 0.05M-0.1M.
 7. Method according to claim 1,wherein the treatment is carried out in an aqueous solution of alkali-and/or earth-alkali hydroxides, or a mixture of these hydroxides, duringa time span in the range of 1 sec-30 min.
 8. Method according to claim1, wherein the treatment is carried out during a time span in the rangeof 5 sec-120 sec.
 9. Method according to claim 1, wherein the treatmentis carried out in an aqueous solution of alkali- and/oralkaline-earth-hydroxides, or a mixture of these hydroxides, at atemperature in the range of 10-30°.
 10. Method according to claim 1,wherein the aqueous solution is a solution of sodium hydroxide. 11.Method according to claim 8, wherein the solution is a solution ofsodium hydroxide at a concentration of of 0.01-0.07 mole, wherein thetreatment is carried out at a temperature in the range 10-30° C. or atroom temperature.
 12. Method according to claim 1, wherein the implantsurface is stored or packaged after the treatment with the aqueoussolution without any post-treatment with an increased temperature or anypost-treatment by rinsing.
 13. Method according to claim 1, wherein theaqueous solution is degassed prior to its use as an immersion bath forthe implant, and optionally is stored in an inert gas atmosphere untiluse.
 14. Method according to claim 1, wherein during the treatmentultrasound is applied to the solution at least period-wise or whereinthe implant is irradiated with UV-light prior to and/or during and/orafter the treatment in the solution.
 15. (canceled)
 16. Method accordingto claim 1, wherein the implant surface is stored and packaged in analkaline solution after the treatment with the aqueous solution, whereinthe alkaline solution is a solution of exclusively alkali- and/oralkaline-earth-hydroxides, or a mixture of these solutions. 17.(canceled)
 18. Method according to claim 16, wherein the alkalinesolution is a solution of sodium hydroxide, at a concentration of0.0001-0.9 mole.
 19. Method according to claim 1, wherein prior to thetreatment in the aqueous solution, a mechanically abrasive surfacemodification is carried out in the form of a blasting-treatment by sandblasting with use of particles with an average particle size of0.05-0.25 mm or 0.25-0.5 mm, with a pressure between 1-10 bar. 20.Method according to claim 1, wherein prior to the treatment in theaqueous solution and possibly after a mechanically abrasive surfacemodification according to claim 19, a chemical surface modification iscarried out, by treatment with concentrated sulphuric acid and/orhydrochloric acid and/or hydrofluoric acid and/or nitric acid ormixtures thereof, at a temperature above room temperature.
 21. Methodaccording to claim 1, wherein the implant, possibly after a priormechanically and/or chemically abrasive surface modification, and whichoptionally has already been treated in an aqueous or organic solution ofalkali- and/or alkaline-earth-hydroxides, is packaged sterilely, and ispackaged in a combination package together with a container whichcontains an aqueous or organic solution of alkali- and/oralkaline-earth-hydroxides, or a mixture of these hydroxides, with atotal concentration of alkali- and/or alkaline-earth-hydroxide in therange of 0.005M-0.5M, and wherein the implant is treated in thecontainer by a method according to claim 1 after release from thepackage only shortly before the insertion into the human body. 22.Combination package comprising at least one sterilely packaged dentalimplant, said implant optionally having undergone an antecedentmechanically and/or chemically abrasive surface modification, and/oroptionally having been treated in an aqueous or organic solution ofalkali- and/or alkaline-earth-hydroxides according to claim 1, andcomprising at least one container with a sterilely packaged aqueous ororganic solution of alkali- and/or alkaline-earth-hydroxides or amixture of these hydroxides, said solution optionally having beendegassed and optionally stored in inert gas, with a total concentrationof alkali- and/or alkaline-earth-hydroxide in the range of 0.005-0.5M.23. Combination package according to claim 22, wherein the containercontains a solution of sodium hydroxide at a concentration of 0.01-0.07mole, wherein this solution optionally has been rinsed with an inert gasprior to the bottling for the removal of CO₂ from the solution. 24.Metallic implant with a hydrophilic surface for the at least partialinsertion into hard tissue such as into a bone and/or into soft tissue,wherein the hydrophilic metal oxide surface is at least section-wisemodified in weakly alkaline manner.
 25. Metallic implant with ahydrophilic surface for the at least partial insertion into hard tissuesuch as into a bone and/or into soft tissue, producible or produced by amethod according to claim
 1. 26. (canceled)
 27. Metallic implantaccording to claim 24, wherein the implant, at least at its surface orentirely, consists of metal oxide and/or metal.
 28. Implant according toclaim 24, wherein the implant contains titanium and/or titanium oxide,which optionally is alloyed with aluminium and niobium, and/or whereinthis alloy contains vanadium instead of niobium.
 29. (canceled) 30.Implant according to claim 24, wherein the hydrophilic surface is atleast area-wise macro-rough, modified by sand-blasting and micro-rough,etched by acid.
 31. Use of an implant produced according to claim 1 oras forming part of a package according to claim 22 as a dental implant,as a crown stub dental implant, as a threaded piece dental implant, ascrew dental implant and/or a pin dental implant.